"TKM" wrote in message
...
"Arfa Daily" wrote in message
...
"Terry" wrote in message
...
On Jul 15, 5:01 pm, "Arfa Daily" wrote:
"Samuel M. Goldwasser" wrote in
...
See:http://repairfaq.cis.upenn.edu/Misc/cflhole1.jpg
This is a ~1 mm hole in the glass near one of the filaments.
Something got hot enough for the glass to melt, and after
that, as they say, the rest was history. 
I've seen this on 3 CFLs in 3 different lamps/fixtures. There are no
known
problems that could account for such nasty behavior. They were all
high
mileage, so perhaps the filament at that end of the lamp opened
resulting
in the discharge going to one post, near the glass, or something.
The CFLs were all from GE but I don't know if they are of the same
ballast/lamp design.
Comments welcome.
--
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Hmmm. Another 'dangerous' aspect of these dreadful devices then. If they
don't send you blind, or provoke epileptic fits, they'll get you by
venting
their mercury vapour !! :-)
Arfa
Yep, soon they'll be considered as dangerous as incandescent lamps
that burn fingers, start fires, explode, send molten glass and
tungsten shooting about and electrocute those who try to change the
bulb. ;-)
Terry
My my, Terry. You do live an interesting and dangerous life ... During
my many years of shuffling around on this little orb of ours, I don't
think I have ever had a domestic incandescent light bulb start a fire,
explode, reach a temperature where the glss could become molten, shoot
molten tungsten at me, or try to electrocute me (how does that one work
then ??). I would have to admit to having scorched (rather than burnt) my
fingers a time or two, but that was down to me employing stupid tactics
for handling them ... d:-)
Arfa
All that stuff has happened usually because (full disclosure) I treated
the lamp rather badly. A drop or two of water on a hot 100 watt GLS lamp,
for example, is sure to cause damage and, probably, fireworks.
I was electrically shocked when I tried to put a 60-watt lamp into a
portable lamp socket with the socket turned on and didn't realize it was
an old portable which didn't have a polarized plug. It's easy to touch
the threaded part of the base when you reach under the shade with the lamp
and try to position it in the socket.
Terry McGowan
Ah ! That all makes more sense now. That last 'problem' can't occur in the
UK as the outer part of the bayonet type bulb holders we normally use here,
is not part of the electrical connection to the bulb, and is either sheilded
with a bakelite type material anyway, or grounded if not. That said, we are
starting to see more lamps with standard ES holders - allbeit shielded - and
a lot more with MES holders that would be quite hard to stick your finger
into to make contact with the centre pin. The wall plugs are not reversible
like some U.S. ones are, but that of course doesn't stop people putting
re-wirable ones on, backwards ... :-\
Arfa